The present invention generally relates to a device providing variable steering responsiveness. More specifically, the present invention relates to a device providing variable steering responsiveness which enhances the steering performance of vehicles, such as tractors.
When an operator of a vehicle, such as a tractor, makes a turn, the vehicle responds by changing the direction of the vehicle. In the conventional tractor, the steering wheel is coupled to a steering linkage which, in turn, is coupled to the front free-rotating wheels. When an operator turns the steering wheel, the front wheels pivot clockwise or counterclockwise. In one type of tractor, commonly known as a zero turn radius tractor, the rear drive wheels rotate independent of one another. The user controls both the speed and direction of this tractor by controlling the motion of the drive wheels relative to one another. In this case, the steering linkage is coupled to the drive wheels. When a user turns the steering wheel, this causes the drive wheels to rotate at different rates, which causes the tractor to turn.
Regardless of the type of tractor, the steering linkage typically includes a gear set having a fixed gear ratio. This fixed gear ratio determines the degree to which the steering linkage moves based on how far the user rotates the steering wheel. For example, for every half turn the user makes, the steering linkage may move four inches, causing the tractor to turn accordingly. Therefore, the tractor has a fixed steering responsiveness or sensitivity.
Depending on the user's level of skill, certain tractors, such as the zero radius turn tractor, can be challenging to steer, especially at relatively low speeds. To assist users, the gear reduction ratio can be increased so that the user's rotation of the wheel has less of an effect on the change in direction. For example, the gear set can be changed so that every half turn causes the steering linkage to move only two inches instead of four inches. Although the steering may no longer be too sensitive for the user, the user will now have to rotate the steering wheel a relatively high number of times in order to make certain turns. The effort required to steer the tractor can be burdensome, inconvenient and tiresome. Furthermore, having a fixed, relatively low steering responsiveness can make it difficult for users to avoid certain driving hazards in certain driving circumstances.
Therefore, there is a need to overcome these disadvantages.